Did that pattern happen only in 1885? Was there a similar pattern at other Liverpool R.C. churches?
Were occupations stated?
Suggestions:
They were marrying before emigrating. Relatives could have come over from Ireland to be witnesses and bid them farewell.
They were seasonal labourers who met during the summer and decided to marry before returning to Ireland for winter. They might have been moving around the county and further if they were agricultural workers or navvies, returning to winter quarters in Liverpool.
The men were construction workers who'd made money during the summer and their girlfriends were keen to get them married before the the money disappeared. (Just too early for the Manchester Ship Canal.)
You may be correct about the clerical moral crusade. There might have been a new priest or bishop or a mission. Did any have children before marriage?
Pauline may be right about a discount. Were any on the same day, a sort of BOGOF offer? There was an old Irish priest in my family's parish who had been trying for a long time to persuade a parishioner to "do the right thing" by the mother of his child - "I'll marry ye for nothin'" he told the man.
February was the popular month for weddings in Mayo, before Lent began. Few during spring and summer until the young men returned from harvest work in England.